int LED1 = 7;
int LED2 = 6;
int LED3 = 5;
int LED4 = 4;
int LED5 = 3;
int LED6 = 2;
int LED7 = 1;
int btn1 = 8;

void setup() {
  // put your setup code here, to run once:
pinMode(LED1, OUTPUT);
pinMode(LED2, OUTPUT);
pinMode(LED3, OUTPUT);
pinMode(LED4, OUTPUT);
pinMode(LED5, OUTPUT);
pinMode(LED6, OUTPUT);
pinMode(LED7, OUTPUT);
pinMode(btn1, INPUT_PULLUP);
digitalWrite(LED1, LOW);
digitalWrite(LED2, LOW);
digitalWrite(LED3, LOW);
digitalWrite(LED4, LOW);
digitalWrite(LED5, LOW);
digitalWrite(LED6, LOW);
digitalWrite(LED7, LOW);
}

void loop() {
  // put your main code here, to run repeatedly:
if(digitalRead(btn1) == LOW)
{
digitalWrite(LED1, HIGH);
delay(500);
digitalWrite(LED1, LOW);
digitalWrite(LED2, HIGH);
delay(500);
digitalWrite(LED2, LOW);
digitalWrite(LED3, HIGH);
delay(500);
digitalWrite(LED3, LOW);
digitalWrite(LED4, HIGH);
delay(500);
digitalWrite(LED4, LOW);
digitalWrite(LED5, HIGH);
delay(500);
digitalWrite(LED5, LOW);
digitalWrite(LED6, HIGH);
delay(500);
digitalWrite(LED6, LOW);
digitalWrite(LED7, HIGH);
delay(500);
digitalWrite(LED7, HIGH);
digitalWrite(LED1, HIGH);
digitalWrite(LED2, HIGH);
digitalWrite(LED3, HIGH);
digitalWrite(LED4, HIGH);
digitalWrite(LED5, HIGH);
digitalWrite(LED6, HIGH);
digitalWrite(LED7, HIGH);
delay(500);
digitalWrite(LED1, LOW);
digitalWrite(LED2, LOW);
digitalWrite(LED3, LOW);
digitalWrite(LED4, LOW);
digitalWrite(LED5, LOW);
digitalWrite(LED6, LOW);
digitalWrite(LED7, LOW);
delay(500);
digitalWrite(LED7, HIGH);
digitalWrite(LED1, HIGH);
digitalWrite(LED2, HIGH);
digitalWrite(LED3, HIGH);
digitalWrite(LED4, HIGH);
digitalWrite(LED5, HIGH);
digitalWrite(LED6, HIGH);
digitalWrite(LED7, HIGH);
delay(500);
digitalWrite(LED1, LOW);
digitalWrite(LED2, LOW);
digitalWrite(LED3, LOW);
digitalWrite(LED4, LOW);
digitalWrite(LED5, LOW);
digitalWrite(LED6, LOW);
digitalWrite(LED7, LOW);
delay(500);
}
}